Current methods for infrared fiber encapsulation into a fiber optic ferrule involve filling the fiber optic ferrule with epoxy. In conventional techniques, the fiber is mechanically held in place by the epoxy, the fiber and epoxy have poor thermal conduction, and the fiber epoxy is not transparent in the infrared (IR) wavelength range wherein the fiber operates. As a result, any stray light not coupled to the fiber or misalignment of the input fiber optic coupling system can result in catastrophic failure of the fiber cable.
In conventional systems, IR fibers are mounted with the same epoxy as silica fibers. IR fibers have greater than 25 times the coefficient of thermal expansion (CTE) of silica (silica: 0.75 ppm/° C., Fluoride: 19 ppm/° C., Chalcogenide: 21 ppm/° C.).
In high power laser systems, distinct material properties of laser system components and the exposure to heat of these components can lead to multiple failure mechanisms not addressed by current techniques. For example, in conventional systems, a specialty fiber cannot be directly clamped. Further, in conventional systems, poorly coupled IR light heats the ferrule, leading to a pistoning effect and stress failure (e.g., radial expansion). Additionally, in conventional systems, clad-guided light heats up the polymer. Light not being tightly coupled to the fiber core can cause some stray light to leak to the fiber cladding and be absorbed by the fiber coating.
Features and advantages of the present disclosure will become more apparent from the detailed description set forth below when taken in conjunction with the drawings, in which like reference characters identify corresponding elements throughout. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The drawing in which an element first appears is indicated by the leftmost digit(s) in the corresponding reference number.